The present invention relates to a magnetic storage unit such as a magnetic disk unit or a magnetic drum unit.
Generally, a recording/reproducing method of a magnetic storage unit constituted by a recording/reproducing magnetic head (to be referred to as a head hereinafter) and a magnetic storage is as follows. That is, at the start of an operation, the head and the surface of the magnetic storage are so set that they are in contact with each other. Thereafter, a space of an air layer is formed between the head and the surface of the magnetic storage by giving a predetermined rotation to the magnetic storage. In this state, recording or reproduction of data is performed. This method is called a contact start stop method. In this method, the rotation of the magnetic storage is stopped at the end of the operation. In this state, the head and the surface of the magnetic storage are in a frictional contact state as when the operation is started. The frictional force produced between the head and the magnetic storage in this frictional contact state wears the head and the magnetic storage. Eventually, this frictional force damages the head and the magnetic storage in some cases. Also, in the above-mentioned frictional contact state, a slight change in attitude of the head sometimes renders the load on the head nonuniform, giving damages to the head and the surface of the magnetic storage.
To prevent the wear of the magnetic storage caused by the contact and slide with the head, a lubricant such as perfluoropolyether is coated on the surface of the magnetic storage, as described in Japanese Patent Laid-Open No. 52-49805. As this perfluoropolyether, those having no functional groups and those having --COOH, --CH.sub.2 OH, --COOCH.sub.3, or a structure represented by the following formula as a functional group have been used. ##STR1##
The above conventional lubricant such as perfluoropolyether, however, has a drawback that if the head and the magnetic storage are kept in contact with each other for long periods of time, they adhere to each other and become difficult to separate. This adhesive force increases the static frictional force or the torque, making it impossible to rotate the magnetic disk or causing plastic deformation of a support spring of the head.